Paranal–Armazones to be Connected to Chilean Power Grid

19 Giugno 2014

ESO has signed an agreement with the company Grupo SAESA to connect its sites at Cerro Paranal and Cerro Armazones to the Chilean electric power grid. The new connection will reduce costs and provide greater reliability and stability, as well as reduce the observatory’s carbon footprint.

The remoteness of the Atacama Desert presents significant challenges to ESO’s operations at its ALMA and Paranal observing sites as they currently have no connection to the Chilean power grid [1], relying instead on their own supply of energy. A power generating station currently operates at Paranal to supply the observatory [2].

Despite the addition of the VISTA and VST survey telescopes, power use has remained stable over the past few years at Paranal. As just one example, a new, more modern laser guide star was recently installed at Paranal (ann11039), effectively reducing the power consumption to less than a tenth of the old laser.

The future needs of the European Extremely Large Telescope (E-ELT) at Cerro Armazones, 22 kilometres east of Cerro Paranal, now warrant a connection to the grid to satisfy the electric power requirements at both sites.

The Chilean government has strongly supported hosting the E-ELT on Chilean land (eso1139). The Chile–ESO agreement on the E-ELT resulted in a new agreement with Grupo SAESA (Sociedad Austral de Electricidad S.A.) for the sites to be connected to a 220 kilovolt substation through a 220/66 kilovolt power transformer, a 66 kilovolt overhead line and a 66/23 kilovolt substation. Both Cerro Paranal and Cerro Armazones will be connected to this 66/23 kilovolt substation by means of two separate 23 kilovolt overhead power lines. A dedicated 23/10 kilovolt power transformer will be installed to adapt the 10 kilovolt system currently operating at Cerro Paranal to the 23 kilovolt of the grid [3]. It is foreseen that the grid connection will be completed in 2018.

With the grid connection at Paranal and Armazones ESO will also become a “regulated electricity customer” of the Chilean Sistema Interconectado Central. The grid connection is one of a series of initiatives ESO is taking to tackle the environmental impacts of its operations as it will not only reduce costs and increase the reliability and stability of the power supply, but also significantly reduce the observatory’s carbon footprint.

In the Chilean interconnected power systems non-conventional renewable energy sources are going to constitute an ever-growing share of the power and energy mixes. Green energy in the grid is strongly supported by the Chilean government, who aims to increase the overall Chilean green energy component to 25% by 2020, with a possible target of 30% by 2030.


[1] The main electricity grid in Chile spanning most of Chile from III Region (Atacama) in the north to X Region (Los Lagos) towards the south is known as the Sistema Interconectado Central (SIC, Central Interconnected System). In the north, the Sistema Interconectado del Norte Grande (SING) extends from XV Region (Arica y Parinacota), through I Region (Tarapacá) and down to the II Region (Antofagasta).

[2] The power generating station at Paranal currently comprises one multi-fuel turbine-generator set (rated about 2.6 Megawatts at the site) and three diesel generator sets (3 x 856 kilowatts). All generators are directly connected to the medium voltage (10 kilovolt) distribution system at the Paranal Observatory.

[3] The power line will connect to the substation to be built close to Paranal. A main high voltage transformer will be used to step the voltage down to the Armazones voltage level. Paranal will be connected through two transformers, so as to retain the ability to provide power to Armazones using the standby generators in case of power failure. A medium voltage substation will also be built at the Armazones summit area.

More Information

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 15 countries: Austria, Belgium, Brazil, Czechia, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning the 39-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.



Roberto Tamai
ESO E-ELT Programme Manager
Garching bei München, Germany
Tel: +49 89 3200 6367

Lars Lindberg Christensen
Head of ESO ePOD
ESO ePOD, Garching, Germany
Tel: +49 89 3200 6761
Cellular: +49 173 3872 621

Riguardo all'annuncio



Grid connection to Paranal and Armazones
Grid connection to Paranal and Armazones
Signing of grid agreement at Paranal
Signing of grid agreement at Paranal